The main difference between the pro and the amateur in aiming pool is the beginner (and most intermediates) bend over the cue ball and fiddle with their aim in place, where the pro not only 1) locks into their stance without changing their aim again (unless they feel they need to change their aim and they stand up, begin once again, and settle in to lock position) but 2) sets their stance to begin with, ensuring the cue ball is locked on the target before they bend to the shot.
Read the previous paragraph 20 times if you must to absorb it fully. More I will not say right now (unless you are paying my usual lesson fee starting at $100 for a session). Although another hint I can give you, as shown on articles elsewhere here at this GuideSite, is this--my stance is designed so that nothing is in the way of making pure center ball contact to sink the next object ball.
That's about as close as I can come to telling you my secret aiming pool system for better billiards!
Have fun and shoot me an e-mail if you want to discuss this further.